What is indicator?

  • (noun): A signal for attracting attention.
    See also — Additional definitions below

More definitions of "indicator":

  • (noun): (chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction.
  • (noun): A device for showing the operating condition of some system.
  • (noun): A number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time.
    Synonyms: index, index number, indicant